class JisuanQi():
    def jia(self, a, b):
        if isinstance(a, (int, float)) and isinstance(b, (int, float)):
            return a + b
        elif a == '' or a is None:
            return ("bunengweikong")
        elif b == '' or b is None:
            return ("bunengweikong")
        else:
            return ("feifa")

    def jian(self, a, b):
        if isinstance(a, (int, float)) and isinstance(b, (int, float)):
            return a - b
        elif a == '' or a is None:
            return ("bunengweikong")
        elif b == '' or b is None:
            return ("bunengweikong")
        else:
            return ("feifa")

    def cheng(self, a, b):
        if isinstance(a, (int, float)) and isinstance(b, (int, float)):
            return a * b
        elif a == '' or a is None:
            return ("bunengweikong")
        elif b == '' or b is None:
            return ("bunengweikong")

        else:
            return ("feifa")

    def chu(self, a, b):
        if b == 0:
            return "被除数不能为零"
        elif isinstance(a, (int, float)) and isinstance(b, (int, float)):
            return a / b
        elif a == '' or a is None:
            return "bunengweikong"
        elif b == '' or b is None or b == 0:
            return "bunengweikong"
        # elif b == 0:
        #     return "被除数不能为零"
        else:
            return "feifa"


if __name__ == '__main__':
    d = JisuanQi()
    # print(d.jia(10, 20))
    # print(d.jia(10, "b"))
    # print(d.jia("@", 10))
    # print(d.jia(10, -10))
    # print(d.jia(1.25, -10))
    # print(d.jia(10, ''))
    # print(d.jian(-10, 10))
    # print(d.cheng(10, 10))
    print(d.chu(5, 0))
